Thanks for the query.
According to your description the possibilities are:
-Vault prolapse : means coming out the vaginal vault
which remained after hysterectomy
-Cystocele: descent of the bladder through the anterior vaginal wall.
-Rectocele: descent of the rectum
through the posterior vaginal wall.
So you better consult gynecologist once and undergo local examination to find out the actual cause of the problem and take treatment accordingly.